CN2829110Y

CN2829110Y - Energy-saving fuel battery stack with hydrogen supplier

Info

Publication number: CN2829110Y
Application number: CNU2005200448211U
Authority: CN
Inventors: 葛栩栩; 王立明; 李创; 李丽; 夏建伟; 章波; 胡里清
Original assignee: Shanghai Shen Li High Tech Co Ltd
Current assignee: Shanghai Shenli Technology Co Ltd
Priority date: 2005-09-06
Filing date: 2005-09-06
Publication date: 2006-10-18
Anticipated expiration: 2015-09-06

Abstract

The utility model relates to an energy-saving fuel cell pile with a hydrogen supplying device, which comprises a film electrode, a current-guiding polar plate, four afflux parent plates, a front end plate, a rear end plate, a fastening pull rod and a hydrogen supplying device that is composed of a hydrogen supplying clamp plate. The hydrogen supplying clamp plate is provided with current-guiding holes for the incoming and outgoing of hydrogen, the current-guiding holes correspond to hydrogen current-guiding holes on the current-guiding polar plate, the side face of the hydrogen supplying clamp plate is provided with hydrogen incoming and outgoing flow passages which are communicated with the hydrogen incoming and outgoing current-guiding holes, and the hydrogen supplying clamp plate is arranged at the middle part of the cell pile. The utility model can more uniformly distribute hydrogen entering a galvanic pile, can be easily assembled and is favorable for improving the operating stability of a cell.

Description

Energy-saving fuel cell stack with hydrogen supply device

Technical Field

The present invention relates to a fuel cell, and more particularly to an energy-saving fuel cell stack with a hydrogen supply device.

Background

An electrochemical fuel cell is a device capable of converting hydrogen and an oxidant into electrical energy and reaction products. The inner core component of the device is a Membrane Electrode (MEA), which is composed of a proton exchange Membrane and two porous conductive materials sandwiched between two surfaces of the Membrane, such as carbon paper. The membrane contains a uniform and finely dispersed catalyst, such as a platinum metal catalyst, for initiating an electrochemical reaction at the interface between the membrane and the carbon paper. The electrons generated in the electrochemical reaction process can be led out by conductive objects at two sides of the membrane electrode through an external circuit to form a current loop.

At the anode end of the membrane electrode, fuel can permeate through a porous diffusion material (carbon paper) and undergo electrochemical reaction on the surface of a catalyst to lose electrons to form positive ions, and the positive ions can pass through a proton exchange membrane through migration to reach the cathode end at the other end of the membrane electrode. At the cathode end of the membrane electrode, a gas containing an oxidant (e.g., oxygen), such as air, forms negative ions by permeating through a porous diffusion material (carbon paper) and electrochemically reacting on the surface of the catalyst to give electrons. The anions formed at the cathode end react with the positive ions transferred from the anode end to form reaction products.

In a pem fuel cell using hydrogen as the fuel and oxygen-containing air as the oxidant (or pure oxygen as the oxidant), the catalytic electrochemical reaction of the fuel hydrogen in the anode region produces hydrogen cations (or protons). The proton exchange membrane assists the migration of positive hydrogen ions from the anode region to the cathode region. In addition, the proton exchange membrane separates the hydrogen-containing fuel gas stream from the oxygen-containing gas stream so that they do not mix with each other to cause explosive reactions.

In the cathode region, oxygen gains electrons on the catalyst surface, forming negative ions, which react with the hydrogen positive ions transported from the anode region to produce water as a reaction product. In a proton exchange membrane fuel cell using hydrogen, air (oxygen), the anode reaction and the cathode reaction can be expressedby the following equations:

and (3) anode reaction:

and (3) cathode reaction:

in a typical pem fuel cell, a Membrane Electrode (MEA) is generally placed between two conductive plates, and the surface of each guide plate in contact with the MEA is die-cast, stamped, or mechanically milled to form at least one or more channels. The flow guide polar plates can be polar plates made of metal materials and polar plates made of graphite materials. The fluid pore channels and the diversion trenches on the diversion polar plates respectively guide the fuel and the oxidant into the anode area and the cathode area on two sides of the membrane electrode. In the structure of a single proton exchange membrane fuel cell, only one membrane electrode is present, and a guide plate of anode fuel and a guide plate of cathode oxidant are respectively arranged on two sides of the membrane electrode. The guide plates are used as current collector plates and mechanical supports at two sides of the membrane electrode, and the guide grooves on the guide plates are also used as channels for fuel and oxidant to enter the surfaces of the anode and the cathode and as channels for taking away water generated in the operation process of the fuel cell.

In order to increase the total power of the whole proton exchange membrane fuel cell, two or more single cells can be connected in series to form a battery pack in a straight-stacked manner or connected in a flat-laid manner to form a battery pack. In the direct-stacking and serial-type battery pack, two surfaces of one polar plate can be provided with flow guide grooves, wherein one surface can be used as an anode flow guide surface of one membrane electrode, and the other surface can be usedas a cathode flow guide surface of another adjacent membrane electrode, and the polar plate is called a bipolar plate. A series of cells are connected together in a manner to form a battery pack. The battery pack is generally fastened together into one body by a front end plate, a rear end plate and a tie rod.

A typical battery pack generally includes: (1) the fuel (such as hydrogen, methanol or hydrogen-rich gas obtained by reforming methanol, natural gas and gasoline) and the oxidant (mainly oxygen or air) are uniformly distributed in the diversion trenches of the anode surface and the cathode surface; (2) the inlet and outlet of cooling fluid (such as water) and the flow guide channel uniformly distribute the cooling fluid into the cooling channels in each battery pack, and the heat generated by the electrochemical exothermic reaction of hydrogen and oxygen in the fuel cell is absorbed and taken out of the battery pack for heat dissipation; (3) the outlets of the fuel gas and the oxidant gas and the corresponding flow guide channels can carry out liquid and vapor water generated in the fuel cell when the fuel gas and the oxidant gas are discharged. Typically, all fuel, oxidant, and cooling fluid inlets and outlets are provided in one or both end plates of the fuel cell stack.

In the prior patent of Shanghai Shenli technology Co., Ltd, "an energy-saving fuel cell" (patent No. 02279853.6), the fuel cell stack is integrated by clamping a front panel and a rear panel. Whereas the hydrogen supply to the fuel cell stack is from the front plate of the stack and the back or front plate is exhausted. The prior art has certain defects:

① when the number of single cells is large, the fuel cell stack is long after being integrated, if the fuel cell stack is integrated by adopting a method of clamping the front and rear panels, the clamping of the front and rear panels is difficult, the front and rear panels are easy to be inclined, the whole stack is inclined, and the assembly is difficult.

② in case of long stack ratio, if hydrogen enters from the front panel, the hydrogen flow will be distributed uniformly among many single cells, which will cause the problem of uneven distribution of hydrogen, thus reducing the stability of stack operation.

SUMMERY OF THE UTILITY MODEL

The purpose of the utility model is to provide an energy-saving fuel cell stack with hydrogen supply device, which can make the hydrogen entering the stack distribute more evenly and reasonably, is favorable for improving the operation stability of the cell and is easy to assemble, in order to overcome the defects existing in the prior art.

The purpose of the utility model can be realized through the following technical scheme:

the energy-saving fuel cell stack with hydrogen supply device includes membrane electrode, flow guide polar plate, flow collecting mother plate, front and back end plates and fastening pull rod, and is characterized by also including hydrogen supply device, said device is formed from hydrogen supply clamping plate, on the hydrogen supply clamping plate the flow guide holes for hydrogen to come in and go out are set, said flow guide holes are correspondent to the hydrogen flow guide holes on the flow guide polar plate, the side surface of the hydrogen supply clamping plate is equipped with hydrogen gas inlet and outlet channels, said hydrogen gas inlet and outlet channels are communicated with the above-mentioned hydrogen gas inlet and outlet flow guide holes, and the hydrogen supply clamping plate is set in the middle portion of cell stack.

The hydrogen supply clamping plate divides the fuel cell stack into a left sub-stack and a right sub-stack, and the number of monocells of the two sub-stacks is equal.

Two sides of the hydrogen supply clamping plate are respectively tightly attached to two current collecting mother plates, and the two current collecting mother plates correspond to the other two current collecting mother plates at the foremost end and the rearmost end of the cell stack.

The front end plate, the rear end plate and the pull rod fasten the cell stack together into a whole.

The left sub-stack and the right sub-stack can be connected in series or in parallel.

Compared with the prior art, the utility model has the advantages of it is following:

① when the number of single cells is large, the fuel cell stack integrated by the hydrogen-supplying clamping plate with good rigidity, high strength and high surface flatness is very firm and not easy to bend.

② the hydrogen enters from the middle clamping plate, flows to the two sides of the stack, diffuses, and then is discharged from the middle clamping plate after being circularly and intensively, thus the hydrogen is more evenly and reasonably distributed in the fuel cell stack.

③ the fuel cell stack can be regulated by clamping the collecting mother board on both sides, connecting the two stacks in series or in parallel (the parallel voltage is half of the series voltage.)

Drawings

Fig. 1 is a schematic structural view of the present invention;

fig. 2 is a schematic structural view of the hydrogen supplying splint of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and specific embodiments.

Examples

As shown in fig. 1 and 2, an energy-saving fuel cell stack with a hydrogen supply device, the length, width and height of which are 275mm × 83mm × 132mm, comprises a single cell 11 consisting of a membrane electrode and a flow guide plate, flow guide mother plates 3, 5, 6, 7, front and

rear end plates

8, 9, a fastening pull rod 10, and further comprises a hydrogen supply device consisting of a hydrogen supply clamp plate 4, wherein the hydrogen supply clamp plate 4 is provided with hydrogen inlet and outlet flow guide holes (a) (B) corresponding to hydrogen guide holes (not shown) on the flow guide plate, hydrogen inlet and outlet flow channels 1, 2 are arranged on the side surface of the hydrogen supply clamp plate 4, the hydrogen inlet and outlet flow channels 1, 2 are communicated with the hydrogen inlet and outlet flow guide holes (a) (B), and the hydrogen supply clamp plate 4 is arranged in the middle of the stack.

The two small sub-stacks of the fuel cell stack of the present embodiment are respectively integrated by 40 single cells 11, and the middle hydrogen supply clamping plate 4 is just placed in the middle of the stack. Two sides of the clamping plate are respectively tightly attached to two current collecting mother plates 5 and 6, and the two current collecting mother plates correspond to the other two current collecting mother plates 3 and 7 which are tightly attached to the foremost end and the rearmost end of the cell stack. And the stack is fastened together into a whole through a front end plate 8, a rear end plate 9 and a pull rod 10. The power of the fuel cell can reach 100-300W. The two small sub-stacks are connected in series to output about 40-80V voltage, and connected in parallel to output about 20-40V voltage. The voltage can be connected according to actual needs. Since hydrogen is supplied from the intermediate plate, the power generation stability of the fuel cell is greatly improved.

Claims

1. The energy-saving fuel cell stack with hydrogen supply device includes membrane electrode, flow guide polar plate, flow collecting mother plate, front and back end plates and fastening pull rod, and is characterized by also including hydrogen supply device, said device is formed from hydrogen supply clamping plate, on the hydrogen supply clamping plate the flow guide holes for hydrogen to come in and go out are set, said flow guide holes are correspondent to the hydrogen flow guide holes on the flow guide polar plate, the side surface of the hydrogen supply clamping plate is equipped with hydrogen gas inlet and outlet channels, said hydrogen gas inlet and outlet channels are communicated with the above-mentioned hydrogen gas inlet and outlet flow guide holes, and the hydrogen supply clamping plate is set in the middle portion of cell stack.

2. An energy saving fuel cell stack with hydrogen gas supply device according to claim 1, wherein the hydrogen supply clamp plate divides the fuel cell stack into left and right partial stacks, and the number of the single cells of the two partial stacks is equal.

3. The energy-saving fuel cell stack with the hydrogen supply device according to claim 1 or 2, wherein two sides of the hydrogen supply clamping plate are respectively attached to two current collecting mother plates corresponding to the other two current collecting mother plates at the frontmost end and the rearmost end of the cell stack.

4. The fuel cell stack with hydrogen supply of claim 1, wherein the front and rear end plates and tie rods fasten the stack together as a single unit.

5. The fuel cell stack with hydrogen supply device of claim 2, wherein the left and right sub-stacks are connected in series or in parallel.